North Korea's foreign minister met briefly with Sweden's prime minister on Friday during a surprise trip to Stockholm that has fuelled speculation about a possible meeting in the Scandinavian country between President Donald Trump and North Korean leader Kim Jong-un.

Swedish Foreign Minister Margot Wallstrom said Sweden is hoping that "we can use our role and also our contacts," but stressed that it is up to the countries concerned to decide "which way we are going." She said,"we value this opportunity to arrange a meeting," though she didn't specify what she meant by that.

Her North Korean counterpart, Ri Yong-ho, arrived late on Thursday and held a first meeting with Wallstrom. On Friday morning, Ri paid what was thought to be a courtesy call to Swedish Prime Minister Stefan Lofven at government headquarters

Trump has agreed to meet Kim by May. So far, North Korea has yet to publicly comment on what it hopes to gain from the talks. Sweden has been rumoured as a possible site for the summit between Kim and Trump, though a truce village on the South Korean side of the Demilitarized Zone between the Koreas is seen as more likely.

Joseph Kim has more for TRT World from Seoul.

Ri's visit to Stockholm, where he once served as a diplomat at the North Korean Embassy, has been shrouded in secrecy.

The Swedish foreign ministry said ahead of his visit that talks would focus on "Sweden's consular responsibilities as a protecting power for the United States, Canada and Australia," but also would address the security situation on the Korean Peninsula." Wallstrom was expected to hold further talks with Ri on Friday, after which her ministry planned to release a statement.

"It is evident that the whole world is following the situation on the Korean peninsula. It is important for everyone's security," Wallstrom told reporters after a parliamentary session on Friday. "We are hoping that if we can use our role and also our contacts, then we will put it to the best use. It is up to the parties to decide which way we are going."

She did not elaborate.

Sweden has had diplomatic relations with North Korea since 1973 and is one of few Western countries with an embassy in Pyongyang. It provides consular services for the United States in North Korea.

The trip by Ri is being closely watched because a huge amount of preparation needs to be done, and there is relatively little time before a theoretical Trump-Kim summit — if it's to happen by May — in which the South Korean President Moon Jae-in would also participate.

Senior South Korean officials who travelled to North Korean capital Pyongyang earlier this month and met with Kim say he is willing to discuss the North's nuclear weapons programme.

That could suggest a potential breakthrough or a fallback to the North's longstanding position that it's willing to get rid of its nuclear weapons if the US guarantees its safety.

In the past, that has meant Washington would have to withdraw all of its troops from South Korea, a condition no US president has been willing to consider.